Bright nickel plating



Patented June 2, 1970 3,515,652 BRIGHT NICKEL PLATING Malcolm J. Law, Greenford, England, assignor to John Preston and Company (Chemicals) Limited, Greenford, England No Drawing. Filed Nov. 25, 1966, Ser. No. 596,750 Int. Cl. C23b /08, 5/46 US. Cl. 20449 13 Claims ABSTRACT OF THE DISCLOSURE Bright nickel deposits are produced by electroplating nickel from an aqueous acidic solution of at least one nickel salt, the reaction product of an acetylene alcohol and an alkali metal perborate, and a water-soluble sulphooxygen compound.

This invention relates to bright nickel plating. The invention is based on the discovery that on reacting in water acetylene alcohols with sodium perborate or any other alkali metal perborate capable of forming a borate derivative and incorporating this material in a nickel plating bath in combination with sulpho-oxygen compounds of the sulphonic acid type, it is found to be very effective for promoting the formation of bright ductile nickel electro-deposits.

According to the invention there is provided a process for producing bright nickel deposits which comprises, electro-depositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved from 0.01 to 1.5 g./l. of a preformed borate compound consisting of the reaction product of an acetylene alcohol and an alkali metal perborate together with a watersoluble sulpho-oxygen compound at a concentration of from 0.5 to 90 g./l.

By preformed we mean that the borate compound is produced before adding it to the plating solution.

The acetylenic alcohol may have the general formula where M is a hydroxyl, hydroxmethyl or hydroxyethyl radical, M is a hydrogen or methyl radical and M is a methyl, hydroxymethyl, hydroxmethyl, methoxymethyl, diethylaminomethyl, morpholinomethyl or hydroxypropyne radical.

This alcohol may also be reacted with the perborate under reflux.

A typical method of reacting acetylenic alcohols with sodium perborate is as follows:

Equal molecular quantities of acetylenic alcohol and sodium perborate are taken. The acetylenic alcohol is made into a 50% solution form in water, placed in a reaction flask and heated to 85-95 C. under a reflux condenser.

The sodium perborate is added gradually until addition of total quantity of perborate has been made, reaction is then continued until gassing ceases and reaction product then gradually changes from a pale straw colour to a deep intense brown colour.

Whilst any of the Water soluble acetylenic alcohols mentioned hereinafter in Table I can be used with success for producing a borate derivative, we have had particular success with 2-butyne-1z4-diol, B-pentyne-l-ol, Z-methyl- 3-butyne-2-0l, l-pentyne-B-ol, 2-pentyne-1:4-diol.

Any of this particular group of chemicals is particularly effected when reacted with sodium perborate, especially 2-butyne-1z4-diol at a concentration of 0.010.5 gm.

of the borate derivative in combination with 0.5 to 30 g./l. of a sulpho-oxygen compound per litre of the nickel solution.

Additions of the brighteners according to this invention have been used in the normal standard Watts type nickel electroplating bath. However, it was also found that they are equally effective in all other acid nickel electroplating baths and, therefore, the invention is applicable to any nickel electro-deposition operation that takes place from an aqueous acidic solution of one or more nickel salts.

Examples of acetylenic alcohols that We have successfully reacted with sodium perborate are given in Table I.

TABLE I 2-propyne-1-ol HCE-CCHZCH 3-butyne-l-ol HCECCHZCHZOH 2-methyl-3-butyne-2-ol l-pentyne-3 -ol HC E CCH (OH) CH CH 3-methyl- 1-pentyne-3-o1 HC =.C C (CH (OH) CH CH 3.S-dimethyl-l-hexyne-3-ol HCEC'C(CH3) (OH)CH (CH 3-ethyl-1-heptyne-3-ol HCEC C (C H (0H) CH CH CH CH l-ethynylcyclohexanol HCEC C(OH) C H 2-butyne-1 :4-diol HC CHZCECCHZOH 4-methoxy-2-butyne-Lol HO CHZCE C CH OCH 1.4-dimethoxy-2-butyne CH OCH CE C CH OCH 3-hexyne-2-5-diol CH CH(OH) CEO CH(OH)CH 4-octyne-3.6-diol CH CH OH(OH) CECCH(OH)CH2CH3 2.5-dimethy1-3-hexyn-2.5-diol (CH3)2C(OH)CEC'C(OH) (CH 3 .6-dimethyl-4-octyne-3.6-diol CH CH C(CH (OH) CECC(CH3) (OH) CH CH 4-diethylamino-2-butyne-l-ol HOCH CEO- CH N(C H 2 4- (N-morpholinyl) -butyne-1-ol E 2O S-pentyne-l-ol CH ECCH CH CH 2.4-hexadyne-1-6-diol HOCH CECCECCH OH Acetylene dicarboxylic acid HOOCCECCOOH Z-pentyne-l :4-diol HO -CH --CEC-CHOHCH As an example of borate compound, 450 g. of 2- butyne-l:4-diol dissolved in water and an equimolecular proportion of sodium perborate were heated to complete reaction. This reaction product can also be used for the production of a semi-bright nickel deposit from a Watts-type nickel solution in conjunction with an acetate.

The compounds listed in Table II are examples of the sulpho-oxygen compounds which are used in conjunction with the reacted product of the acetylenic alcohols.

TABLE II (1) Mononuclear aromatic sulphonic acids and alkali metal ammonium, magnesium and nickel salts thereof.

Benzene monosulphonic acid C H SO H Sodium benzene monosulphonate C H SO Na Nickel benzene monosulphonate (C H SO Ni Sodium para-toluene monosulphonate CH C H SO Na Para-chlorobenzene sulphonic acid ClC H SO H Sodium para-bromobenzene sulphonate BrC l-I SO Na 1:2, dichlorobenzene sulphonic acid C1 C H SO H 1:2, or 2.5 dichlorobenzene sulphonate sodium salt Cl C H SO Na Meta-benzene disulphonic acid C H (SO H) Sodium meta benzene disulphonate C H (SO Na) Ortho-sulphobenzoic acid monoammonium salt HOCOC H SO NH 1-amino-2.5-benzene disulphonic acid Sodium thiophene sulphonate C H S-SO Na 4 Ortho-aminobenzene sulphonic acid H NCgH SO H Thiophene sulphonic acid C H S-SO H (2) Mononuclear aromatic sulphonic acids, and alkali 2.-4(-pyridyl) -ethyl sulphonic acid C H N-CH CH SO H metal, ammonium, magnesium and nickel salts thereof. In all cases the free sulphonic acids and their alkali Sodium benzene sulphonate C H SO Na metal, ammonium, magnesium and nickel salts are the full equivalents of each other in this invention.

Of the compounds in Table II we found the sodium Sodium para-toluene sulphonate CH C H SO Na Mononuclfiar aromatic sulphonamides and imides' salt of naphthalene lz3z6 trisulphonic acid particularly Benzene sulphonamide s s z z effective when used at between 1-30 g./l. Para-toluene sulphonamid? CH3C6H4SO2NI I'2 If a group B material is used alone only a poor semi- OIthO-beIIZOiC sulphonamlde G 4 2 10 bright deposit is obtained. When'used in conjunction with Benzyl sulphonamide C6H5CH2SO2NH2 the borated product, brilliant fully bright deposits are Benzene sulphydloxamic acid s 5 2 obtained. Good levelling is also obtained from using this N.N. dimethyl para-toluene sulphonamide product Ii ti i 2 3)2 The concentration of the borated product is very Wide, dical'boxyethyl benzene sulphonamlde a certain minimum concentrated of the compounds of 6 5 2 2 4 )2 Table II being required depending on the concentration of group A" compounds of Table I.

(4) Binuclear aromatic sulphonic acids and alkali Brilliant nickel deposits may be obtained in accordmetal, ammonium, magnesium and nickel salts thereof. ance with this invention, using electrolytes listed in Z-naphthalene monosulphonic acid C H SO H Table III.

TABLE III.-BATH CONCENTRATIONS IN GRAMS PER LITRE Bath. 1 2 3 4 5 6 7 Nickel sulphate, NiSOflHzO Nickel chloride, N iCl26HzO Nickel formate, Ni(OOCH)12 O Nickel'fluoborate,Ni(BF4)2 Nickel sulphamate, N i(0 SNH Sodium chloride, N l

Boric acid, H3130; 7. 5 2-butyne 1:4 diol borate derivative (0. 2-0. 4) 0.2 0.2 .2 0.25 1,3,6 naphthalene trisulphcnic acid sodium salt 1-5 4. 0 4. 0 4. 0 2. 0 Temperature, C -60 50 50 50 50 1:5 or 2:7 naphthalene disulphonic acid C H (SO H) An example of the type of nickel solution that has been 1:5 or 2:7 naphthalene disulphonic acid nickel salt used with particular success in accordance with this in- C H (SO Ni vention is one containing: Naphthalene trisulphonic acid C H (SO H) Naphthalene trisulphonic acid trisodi-um salt NI JH O g./l 280 C10H5(SO3 Na)3 --g-/1 Diphenyl pp-disulphonic acid.HSO C H C H SO H 40 3 0 g./l 4O Z-naphthol 3:6 disulphonic acid. IIOC ,H (SO I-I) N phthalene trrsulphomc acid g./l 10 2-naphthol 3:6 disulphonic acid sodium salt HOC10H5(SO3Na)2 v Sodium salt:0.25 g./l. of the acetylenic borate reaction 1 1 -3; ;g i acid produce pI-I-3.6 and operated at 50 C. at 40-60 amperes H2N.C10H4(SO3H)3 per square foot.

Brilliant nickel deposits may be obtained in accordance with the invention from the electrolytes listed in Table 4 and Table 5.

(5) Heterocyclic sulphonic acids and alkali metal ammonium, magnesium and nickel salts thereof.

TABLE 4.BATH CONCENTRATIONS IN GRAMS PER LITRE Bath 1 2 3 4 6 6 7 Nickel sulphate, NiS O47N7O 240-330 330 330 330 240 Nickel chloride, NiClzGHgO 30-45 O-37. 5 0-37. 5 30 N ickel formate, Ni(0 O CH) 221120. 45 Nickel fiuoborate, Ni(BF4)1 Nickel sulphamate, Nl(O3SNI'Ig) Sodium chloride, NaCL Sodium bromide, NaBr Boric acid, H3130; (satura so Reaction product or 2-butyne-1:4-dio1 and sodium perborate. 005-0. 3 005-0. 3 005-0. 3 005-0. 3 005-0. 3 005-0. 3 005-0. 3 O-Sulphobenzoic acid imide sodium gm./ltr. 1-10 1-10 1-10 1-10 1-10 1-10 1-10 Temperature, C 50-52 52 52 52 52 52 52 2 propene 1 sulphonic acid sodium salt 0. 05-1. 5 0. 1-1. 5 0. 02-1. 5 0. 1-1. 5 0. 1-1. 5 0. 1-1. 5 0. 05-1. 5

TABLE 5 Bath 1 2 3 4 5 6 1 Nickel sulphate, NiSOflHzO gmJltr 50/100 50/100 50/100 50/100 50/100 Nickel chloride, NiClzfiHzO gnL/ltr..- /300 150/300 150/300 150/300 150/300 150/300 150/300 Nickel for-mate, N i(OOCH)z2H O 45 Nickel fluoborate, Ni(B F4): Nickel sulphamate, N 1(O SN Hm."

Sodium chloride, N 2.01 Sodium bromide, NaBr Boric acid, H 13 0 saturation solution 50- 50- 50- 50- 50- 50- 50- Reaction product of 2-butync-1:4 diol and sodium perborate 005-. 3 005-. 3 005-. 3 005-. 3 005-. 3 005-. 3 005-. 3 O-Sulphobenzoic acid imide sodium salt gmJltr. 1-10 1-10 1-10 1-10 1-10 1-10 1-10 Temperature, C 50-52 50-52 50-52 50-52 50-52 50-52 50-52 2-propene-1- sulphonic acid sodium salt 0. 05-1. 5 0. 1-1. 5 0. 02-1. 5 0. 1-1. 5 0. l-1. 5 0. 1-1. 5 0. 05-1. 5

According to one desirable process in accordance with this invention the solution comprises at least one nickel salt, in which is dissolved from 0.00156 to 0.3 g./l. of a reaction product of Z-butyne-l: 4-diol and sodium perborate and 0.1 to 1.0 g./l. 2-propene-l-sulphonic acid in the presence of between 50 g./l. and a saturated solution of boric acid and 0.5 to 80 g./l. of a water soluble sulphooxygen compound selected from the group consisting of mononuclear and binuclear aromatic sulphonic acids, alkali metal, ammonium, magnesium and nickel salts of said acids and mononoclear aromatic sulphonamides and sulphonimides or salts of such amides and imides.

Examples of the type of nickel solutions that were used with particular success in accordance with this invention are those containing:

(1) 280 g./l. NiSO 7I-I O: 40 g./l. NaCl: 56.25 g./l. H BO 3S g./l. naphthalene trisulphonic acid-sodium salt. pH 3,6, temp. 48-56 C. Current density--40-l00 amps/square foot. 0.3 g./l. of reaction product of Z-butyne l: 4 diol and sodium perborate: 2 propene 1- sulphonic acid-l.0 g./l.

(2) 280 g./l. NiSO 7H O: 40 g./l. NaCl: 56.25 g./l. B 130 2 g./l. of o-sulphobenzoic acid imide sodium salt. pH 3.6. Temp. 4856 C. Current density-40-100 amps/square foot. 0.3 g./l. of reaction product of Z-butyne-l: 4-diol and sodium perborate: Z-propene l-sulphonic acid-1.0 g./l.

I claim:

1. A process for producing bright nickel deposits which comprises electro-depositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved from 0.00156 to 1.0 g./l. of a preformed borate compound consisting of the reaction product of the reaction of equal molar amounts of an acetylene alcohol and an alkali metal perborate at a temperature of 85-' 95 C.; together with a water-soluble sulpho-oxygen compound at a concentration of from 0.5 to 90 g./l.

2. A process according to claim 1, wherein the acetylenic alcohol is 2-butyne-1z4-diol. I

3. A process according to claim 2, wherein the amount of reacted 2-butyne-l:4-di0l and sodium perborate is in the range of 0.01 to 0.5 g./l. and the amount of the sulphooxygen compound is in the range of 0.5 to 80 g./l.

4. A process as claimed in claim 1 wherein the acetylenic alcohol is 3-pentyne-l-ol.

5. A process as claimed in claim 1 wherein the acetylenic alcohol is 2-methyl-3-butyne-2-ol.

6. A process as claimed in claim 1 wherein the acetylenic alcohol is 1-pentyne-3-ol.

7. A process as claimed in claim 1 wherein the acetylenic alcohol is 2-pentyne-lz4-diol.

8. A process according to claim 1 wherein the sulphooxygen compound is selected from a group consisting of mononuclear and binuclear sulphonic acids, heterocyclic sulphonic acids, mononuclear aromatic sulphonic acids, alkali metal, ammonium, magnesium and nickel salts of said acids, and mononuclear aromatic sulphonamides and sulphonimides.

9. A process according to claim 1 wherein the sulphooxygen compound is naphthalene trisulphonic acid sodium salt.

6 10. A process of producing bright nickel deposits which comprises electrodepositing nickel from an aqueous acidic solution of at least one nickel salt in which there is incorporated from 0.00156 to 0.3 g./l. of the borate reaction product of the reaction of equal molar amounts of an acetylenic alcohol and with sodium perborate at a temperature of 85-95 C., the said acetylenic alcohol having the general formula where M, is a hydroxyl, hydroxymethyl or hydroxyethyl radical, M is ahydrogen or methyl radical and M is a methyl, hydroxymethyl, hydroxyethyl, methoxymethyl, diethylaminomethyl, morpholinomethyl or hydroxypropyne radical and 0.5 to 90 g./l. of a water soluble sulphooxygen compound.

11. A process for producing bright nickel deposits which comprises, electro-depositing nickel from an aqueous acidic solution of at leastone nickel salt, in which is dissolved from 0.00156 to 0.3 g./l. of a borate reaction product of the reaction of equal molar amounts of 2-butyne-l :4 diol and sodium perborate at a temperature of 85-95 C. and 0.1 to 1.0 g./l. 2-propene-l-sulphonic acid in the presence of between 50 g./l. and a saturated solution of boric acid and 0.5 to g./l. of a water soluble sulpho-oxygen compound selected from the group consisting of mononuclear and binuclear aromatic sulphonic acids, alkali metals, ammonium, magnesium and nickel salts of said acids and mononuclear aromatic sulphonamides and imides or salts of such amides and imides.

12. A process for producing bright nickel deposits which comprises, electro-depositing nickel from an aqueous acidic nickel solution of at least one nickel salt in which there is dissolved from 0.00156 to 0.3 g./l. of the borate reaction product of the reaction of equal molar amounts of 2-butyne-lz4-diol and sodium perborate at a temperature of -95 C., 0.1 to 1.5 g./l. Z-propene-lsulphonic acid, 50 g./l. to a saturated solution of boric acid and 0.5 to 80 g./l. of naphthalene trisulphonic acidsodium salt.

13. A process for producing bright nickel deposits which comprises, electro-depositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved at least 0.3 g./l. of the borate reaction product of the reaction of equal molar amounts of 2-butyne-lz4-diol and sodium perborate at a temperature of 85-95 C., 0.1 to 1.0 g./l. 2-propene-l-sulphonic acid, at least 50 g./l. boric acid and l to 10 g./I. of orthosulphobenzoic acid imide sodium salt.

References Cited UNITED STATES PATENTS 3,245,887 4/1966 Passal et a1 204-49 JOHN H. MACK, Primary Examiner G. L. KAPLAN, Assistant Examiner 

